In conventional lymphedema diagnosis, for example, scintigraphy is used, but there is a problem in that it is difficult to obtain local image information of an affected limb. Also, there is a problem in that an inspection is complex. On the other hand, a technique capable of observing a detailed state of lymphedema through fluorescence observation using a fluorescent dye such as indocyanine green in real time has recently been developed. In the fluorescence observation, observation of the fluorescence pattern is performed by irradiating an observation object with excitation light for exciting the fluorescent dye after the fluorescent dye is injected into the observation object.
As a fluorescence observation device used in the fluorescence observation, for example, there is a fluorescence observation device disclosed in Patent Literature 1. This fluorescence observation device is configured to include a light source which generates excitation light, an acquisition unit which acquires fluorescence information generated from an observation object by irradiation with the excitation light, an acquisition unit which acquires fluorescence information generated from a residue of the observation object by irradiation with the excitation light, and a correction unit which corrects fluorescence information so that fluorescence from the residue is suppressed.